This proposal expands the research scope of the parent grant (R01 AG033906) by investigating biological markers reflecting predisposing factors for and the stress-related consequences of chronic pain. Consistent with the OppNet priorities, this proposal targets an improved understanding of the complex interaction of biopsychosocial factors on health outcomes. Two biological measures associated with psychosocial stress, accelerated aging, and morbidity;telomere length (TL) and telomerase activity (TA), will be incorporated into the study design which includes assessment of pain severity, functional limitations, and measures of pain-related psychological risk factors and psychosocial stress (e.g., perceived stress and experiences of discrimination). The overall aim of this competitive revision is determine the influence of chronic pain and psychosocial stress on TL and TA among older African American (AA) and non- Hispanic white (NHW) individuals with knee osteoarthritis (OA) as well as age and ethnicity-matched healthy controls. The relationships between telomere measures, experiences of chronic pain, behavioral and social factors, and potential ethnic differences, have not yet been investigated. The goal of this competitive revision is to better understand the interaction between biological processes and behavioral and social variables in ethnically diverse older adults with and without chronic OA-related pain, to determine the utility of TL and TA as tools in assessing system burden resulting from chronic pain and/or other biopsychosocial variables, and to identify vulnerability and resilience factors. PUBLIC HEALTH RELEVANCE: Evidence suggests that chronic psychosocial stress may be a significant contributor to pain- related ethnic group differences. We intend to evaluate biological markers of psychosocial stress and chronic pain in a large multi-ethnic sample of patients with and without knee osteoarthritis. This information will proved an improved understanding of inter-individual variability in chronic pain, help identify behavioral and social targets for prevention and treatment, and provide a mechanism for evaluating the efficacy of clinical interventions.